It’s true that Obama seemed to be widening his lead to a significant margin in the days leading up to the debate. But a lot of that may have reflected the bump Obama received from his convention. Yes, Obama’s debate performance was a disaster. But in many ways, the crucial element at the debate was not just Obama’s terrible showing; it was Mitt Romney’s excellent one. After months of operating from a failed theory of the race — which led him to make the race only about Obama — Romney made a strong affirmative case for himself and his policies. It was full of distortions and evasions about the true nature of his actual agenda, but it was unquestionably a politcally effective presentation of the case for his candidacy, rather than simply an indictment of the Obama presidency.

We will never know whether the polls would have tightened less than they have now if Obama hadn’t failed so miserably to rebut Romney’s case for himself. And it’s true that Romney’s surge has to some degree defied expectations. But a tightening was always inevitable. This race was never going to be easy for Obama to win. The fundamentals have proven durable: A weak recovery, which ensures a very tough contest with perhaps a slight edge to the incumbent.

In Ohio...they say that they still believe the president holds a real lead and that they remain narrowly ahead in a number of other states. They argue that the big margins of two weeks ago were always destined to tighten, given everything that is known about these states from past campaigns. The debates, they say, accelerated a process that was likely to happen sometime in October.

But from their research, the race has begun to settle down. Romney is not continuing to gain ground. “Romney has consolidated some of the gains he was going to get anyway,” said White House senior adviser David Plouffe. “We weren’t going to win battlegrounds by 10 points.”

This may sound like spin, but the Obama team has predicted a tight finish for months. Plouffe told me way back before the conventions that the Obama team believed this will be exceptionally close until the end. He added then that if Obama can hold a slim two to three point lead in enough key states, the remaining undecided voters won’t break to Romney in the numbers he’ll need. Given what we know right now, this is still eminently doable. Yes, it’s possible that Romney’s bounce will continue and make him the confirmed favorite. But for now, all indications are that this has simply become the very close race it was always likely to become.

Mr. Romney’s campaign insists he has no control over his investments since they are held in a blind trust. That said, a confidential prospectus for one of the Bain funds, obtained by The New York Times, promotes China as a good investment for some of the same reasons that Mr. Romney has said concern him: “Strong fundamentals” like manufacturing wages 85 percent lower than what Americans earn, vast foreign exchange reserves and the likelihood that China will surpass the United States as the world’s largest economy.

The Obama campaign may see this as an opening to revive the Bain narrative, and hammer it today to prevent Romney from closing the gap in Ohio, which has been pounded by outsourcing and has seen a rebound in the auto industry that has helped keep the jobless rate below the national average.

“My opponent sees these programs as breeding ‘dependency.’ We’ve heard Governor Romney say much the same thing behind closed doors. This may have been a legitimate debate...in the 19th century. But shredding our safety net is not what America needs at a time when global competition and rapid technological change are leaving Americans increasingly vulnerable.”

The forecast model is not quite ready to jump on board with the notion that the race has become a literal toss-up; Mr. Romney will need to maintain his bounce for a few more days, or extend it into high-quality polls of swing states, before we can be surer about that. But we are ready to conclude that one night in Denver undid most of the advantage Mr. Obama had appeared to gain in September.

A batch of swing state polls is due out today; they will begin to tell us whether Romney’s bounce — which looks to be a bit higher than three points, not quite as large as Obama’s pre-convention lead — is durable or receding. Though Romney is edging ahead in national polling averages, we won’t know how real that is until the polling no longer includes the two or three days just after the debate.

* Nancy Pelosi: It’s all about unmarried women: Pelosi gives Joe Biden one word of advice for the debate: “Women.” She points out that unmarried women are key to this election, which means he and Obama should hammer home messages about health care, the Lily Ledbetter Act, and the Violence Against Women Act, which Joe Biden authored.

As Stan Greenberg told me yesterday, Obama failed at the debate to connect with unmarried women and explain to them clearly how he would improve their lives.